Together with a hydrolase component (EC 3.1.2.2/EC 3.1.2.14) and a reductase component (EC 1.2.1.50), this enzyme forms a multienzyme fatty acid reductase complex that produces the long-chain aldehyde substrate of the bacterial luciferase enzyme (EC 1.14.14.3). The enzyme activates free long-chain fatty acids, generated by the action of the transferase component, forming a fatty acyl-AMP intermediate, followed by the transfer of the acyl group to an internal L-cysteine residue. It then transfers the acyl group to EC 1.2.1.50, long-chain acyl-protein thioester reductase.